Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of micro-organisms contaminating the upper intestinal contents of malnourished children on intestinal absorption of 3-0 methyl-alpha-D-glucopyranose (3-M.G.) and oleic acid was studied in rats in vivo. Oleci acid absorption was unaffected by non-pathogenic E. coli but decreased by E. coli 0111, Salmonella paratyphi B., Shigella sonnei and Candida sp. This effect was probably explained by intestinal secretion diluting the test solution leading to a decreased diffusion gradient for solubilised fatty acid. Inhibition of sugar absorption occurred with bacterial suspensions of Staphylococcus aureus, Streptococcus faecalis, E. coli and Candida sp. and cell-free preparations of Staphylococcus aureus, Streptococcus faecalis, a non-pathogenic E. coli, Proteus sp., Klebsiella sp., Pseudomonas sp. and Candida sp. These effects were not explained by dilution of the test solution. This indicates that numerous micro-organisms and, in some instances, their cell-free preparations can interfere with intestinal active sugar transport. These findings may be relevant to the production of malabsorption in malnourished children who have a wide variety of micro-organisms contaminating their upper intestinal contents.
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PMID:Effect of enteric micro-organisms on intestinal sugar and fatty acid absorption. 60 64

Nine of 14 cases of giardiasis and severe malabsorption were found to have numerous bacteria adjacent to the mucosa and within luminal fluid samples from the upper jejunum. Three species of enterobacteria (Klebsiella pneumoniae, Enterobacter cloacae and E. hafniae) were cultured from eight patients and from only one were Bacteroides isolated. Enterobacteria were not cultured from seven of eight patients who had giardiasis but only mild malabsorption (of xylose only) nor from seven patients without malabsorption. Intestinal colonization by enterobacteria may make an important contribution to the development of malabsorption in patients with giardiasis.
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PMID:Bacterial colonization of jejunal mucosa in giardiasis. 63 72

The mechanism of bacterial uptake of vitamin B(12), the spectrum of microorganisms capable of such uptake, and the factors involved were the subject of this study. Bacterial uptake of vitamin B(12) was found to be at least a two stage process. A primary uptake phase which was rapid (1 min or less), pH dependent, nontemperature dependent, did not require viable organisms and was insensitive to either the metabolic inhibitor dinitrophenol or to the sulfhydryl inhibitor N-ethyl-maleimide. Protein denaturation (formalin treatment or autoclaving) abolished all B(12) uptake. This primary uptake phase is thought to represent adsorption to binding or "receptor" sites on the cell wall. Second stage uptake was slower, pH and temperature dependent, required living bacteria, and was abolished by either dinitrophenol or N-ethyl-maleimide. This phase is dependent upon metabolic processes and may reflect transfer of B(12) from surface "receptor" sites into the bacterial cell. Although differences among organisms were observed in total 1 hr uptake, number of surface "receptor" sites, and relative avidities for B(12), all organisms except Streptococcus fecalis shared the two stage mechanism. Two Gram-positive organisms. Bacillus subtilis and Group A streptococcus, demonstrated the highest 1 hr vitamin B(12) uptake values; Gram-negative bacteria required 2,000-10,000 the number of organisms for comparable uptake. Binding constants (K(m)) varied from 5.05 +/-1.67 x 10(-10)M for B. subtilis to 6.18 +/-3.08 x 10(-9)M for Klebsiella pneumoniae which approximate the Km for human intrinsic factor (0.38 x 10(-10)M). Competition between bacteria and intrinsic factor for vitamin B(12) may be inferred from the similarity of these constants. These observations suggest that a variety of enteric and nonenteric organisms, not requiring exogenous B(12), may play a role in the pathogenesis of the vitamin B(12) malabsorption found in the intestinal bacterial overgrowth syndromes.
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PMID:Vitamin B12 uptake by intestinal microorganisms: mechanism and relevance to syndromes of intestinal bacterial overgrowth. 499 53

The bacterial flora of the upper intestine has been examined in symptomatic expatriate adults with mild tropical malabsorption, without steatorrhoea, persisting for many months after return to a western environment. Seven of the 11 patients had enterobacteria in luminal fluid or mucosal samples in numbers ranging from 10(3) to 10(8) per ml or per g. The most common isolate was Klebsiella pneumoniae (in four cases); Citrobacter freundii, Serratia marcescens and Pseudomonas spp. were also detected. The signficance of bacterial colonization in the pathogenesis of mild tropical malabsorption is discussed.
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PMID:Bacterial colonization of the upper intestine in mild tropical malabsorption. 721 Jan 30